1. Field of the Invention
The present invention relates to water heating systems and, more particularly, to a water heating system that employs a vapor compression system using carbon dioxide as the refrigerant.
2. Description of the Related Art
Water heating systems that utilize a heat pump cycle, i.e., a vapor compression system, having carbon dioxide as the refrigerant are known in the art. Such systems typically include a compressor that compresses carbon dioxide from suction pressure to a supercritical discharge pressure. The compression of the carbon dioxide to the discharge pressure elevates the temperature of the carbon dioxide. The hot, high pressure carbon dioxide is then supplied to a heat exchanger in which the carbon dioxide is cooled and water is heated.
Although such water heating systems are known, an improved water heating system that employs a vapor compression system having carbon dioxide as the working fluid is desirable.